Conductor tab interconnecting arrangement for terminal blocks



April 23, 1963 R. L. LINN 3,087,137

CONDUCTOR TAB INTERCONNECTING ARRANGEMENT FOR TERMINAL BLOCKS Filed July10, 1961 fig. 4.

11 3 z3 Z EKMM a1 RICHARD L. LINN United States The present inventionrelates generally to terminal blocks adapted for use in electricalcircuits and systems. More specifically the invention deals with a newand improved terminal block, a new and improved conductor tabinterconnecting arrangement for use in a terminal block, and a new andimproved electrical conductor tab adapted for use in the newarrangement.

'lerminal blocks are widely used as a centralized source of attachmentof a plurality of electrical circuits. A terminal block of the typedisclosed in my Patent No. 2,965,872 is very useful in eificientlyaccommodating the centralized connection of a plurality of electricalcircuits and services. In such a block, a plurality of electricallyinterconnected metallic tabs having tongue-like portions are mounted ina readily moldable plastic block housing with tongue portions projectinginto separated recesses which are in communication with surface areas ofthe housing. The interconnected tabs are readily formed by die stampingmetallic strips and the resulting strip-like members are provided withany desired number of tonquelike portions. Selected strips are readilymounted in the block housing to provide for the requisite number of wirelead termination for a plurality of independent circuits. While thisarrangement provides for adequate versatility by reason of the installerbeing provided with a variety of strips having varying numbers of tongueportion-s, the arrangement does require the manufacture and stocking ofa variety of such strips.

It is an object of the present invention to provide a new and improvedterminal block for multiple electrical circuit and wire lead terminationuse.

Another object is to provide a new and improved conductor tabinterconnecting arrangement in a terminal conductor unit, sucharrangement permitting ready and unlimited variation of plural circuitarrangement and wire lead termination relative thereto.

Still a further object is to provide a new and improved electricalconductor tab of a design and adapted for use in such a manner that tabstandardization is possible not only from the standpoint of manufacturebut also with regard to an unlimited variety of operational uses.

Other objects not specifically set forth will become apparent from thefollowing detailed description of the invention made in conjunction withthe accompanying drawing wherein:

FIG. 1 is a perspective of a form of terminal block incorporating theprinciples of the present invention therein;

FIG. 2 is a plan view of the base member of the block of FIG. 1 with thecover member removed;

FIG. 3 is a perspective of the tab forming a part of the invention; and

FIG. 4 is an enlarged transverse section of a portion of the block takengenerally along line 4-4 in FIG. 2.

The terminal block of the invention comprises a base member 11preferably molded from plastic material and a cover member 12 in theform of an insulating plate suitably attached to the base member 11 byfasteners 13. As best shown in FIG. 2 the base member 11 is formed withraised block-like end portions 14 between which is formed a plurality oflaterally extending wire lead receiving recesses 15. In the form ofblock illustrated, the recesses 15 are vertically directed in the basemember atent ice 11 and extend inwardly thereof from communication withopposite side margins of the base member. The recesses 15 are basicallydefined by upstanding wall segments 16 formed during molding of the basemember 11. The innermost end of each recess 15 is substantially closedoff by reason of a longitudinally extending enlarged inner end portions17 of adjacent wall sections 16. Adjacent enlarged end portions 17define therebetween laterally directed slots 18 through which oppositeend portions of electrical conductor tab-s 19 extend.

The enlarged end portions 17 of the wall sections 16 also cooperativelydefine a slot 20 which extends longitudinally of the base member 11between laterally aligned recesses 15. The slot 20 in the base thereofincludes a plurality of longitudinally spaced block-like portions 21extending between juxtaposed end portions 17 of the wall sections 16.Between the block-like portions 21 the base of the slot 20 is formedwith upstanding bead segments 22 which extend across juxtaposed slots 18in communication with transversely aligned recesses 15. The beads 22 areformed with convex upper surfaces for a purpose to be described.

FIG. 3 best illustrates the special electrical conductor tab 19 forminga part of the invention. This tab is formed from a single piece of fiatmetallic material and is provided with a central block-like mountingportion 23 having integrally formed therewith a pair of oppositelydirected lead attachment tongues 24. Each tongue 24 is dimensioned to bereceived in a recess 15 in spaced relation with all Wall surfacesthereof including the adjacent covering surface of the cover member 12The outermost edge of each tongue 24 is formed with beveled surfaceportions 25 to provide for readily receiving thereon a suitable form ofwire lead connector 26 shown in FIGS. 2 and 4. The tongues 24 may beformed with dimple-like depressions 27 centrally thereof to receivetherein corresponding projections formed in a lead connector 26 in theknown manner to provide for a tight electrical connection between thetongues and connectors. The central mounting portion 23 of the tab 19along opposite side margins is formed with projecting shoulder portions23. These portions are each formed with a centrally locatedsemi-circular slot or recess 29 of a configuration conforming with thatof the bead segments 22 or" the base member 11.

FIG. 4 best illustrates the operative mounting of a tab .19 in the basemember 11. As previously described, the tab extends across thelongitudinal slot 20 and through aligned transverse slots 18 to placethe oppositely directed tongues 24 thereof in transversely alignedrecesses 15. The tab 19 is maintained in vertical position asillustrated in FIG. 2 by the receiving of the mounting portion 23thereof in the aligned transverse slots 18. These slots provide adequateclearance to permit ready insertion of a tab 19 while holding the sameagainst any appreciable tilting. The lowermost shoulder 23 of themounting portion 23 is received flush against the bottom surface portionof the base member 11 with the head 22 being inserted in the associatedrecess 29. The bead 22 functions to prevent lateral movement or play ofthe tab 19 when mounted in the base member ll.

FIGS. 2 and 4 illustrate a typical connection of a wire lead 30 with atab 19 by means of a connector 26. The lead 30 is of known typeincluding insulation covered wire strands with bare ends 31 thereofbeing clamped by segments 32 of the connector 26. Additional segments 33clamp the insulation covering of the lead 3!} to prevent strippingthereof. The connector end engaged with the tongue 24 of the tab 19 isprovided with resilient leaf portions 34 of known type, this end of theconnector being dimensioned to be readily received in a recess 15 of theblock 10.

7 With this arrangement a plurality of wire leads 30 may be readilyconnected to tabs 24 as well as readily disconnected therefrom.

As previously described, one of the recesses 29 of the tab 19 weaves abead segment 22 therein to fix the tab in the base memberll. 'Theremaining recess is thus exposed along the top surface of the tab in itsmounted position in the base member 11. A single strand bare wiresegment 35 is inserted in the uppermost recess 29 of a tab 19 andextends longitudinally of the base member 11 in parallel relation withthe slot 20 thereof into similar engagement with one or more tabs 19.FIG. 2 illustrates the use of wire segments 35 in interconnectingseparate series of tabs 19, each series including any desired number ofimmediately adjacent tabs. The diameter of the Wire segment 35 is suchthat the same is snugly received or forced into the recess 29 of a tab19 to prevent inadvertent displacement therefrom and provide for anefficient electrical conducting connection. Thus any number of tabs 19may be electrically interconnected in a single circuit by properselection of the length of wire segment 35 installed in the block 10.Each Wire segment may be readily measured and cut on the job duringinstallation of the block to meet a variety of requirements. All of thetabs 19 are of the same design thus providing for uniformity inmanufacture as well as uniformity in stocking of adequate components andparts by the installer. Each wire segment 35 is readily inserted in theassembly without the need of special tools and with proper snug,crimp-like fitting of the wire segment in the recesses 29 of the tabs19, displacement thereof is prevented. Following desired interconnectionof the plurality of tabs 19 in the base member 11, the cover member 12is applied by use of the fasteners 13 and the terminal block 10 is fullyassembled. Any number of tabs 19 may be used in a single block and onlythe total number of tabs intended for use need be installed.

The particular form of terminal block 10 illustrated and described isonly one of several forms with which the unique tab interconnectingarrangement of the invention may be used. The vertical positioning ofthe tabs 19 in the terminal block to permit ready accommodation of theinterconnecting wire segment feature also permits increased spacingbetween the tabs thus allowing the use of circuits of higher potential.In this regard, the wall portions 16 may be of rather substantialthickness without resulting in any appreciable Wasted space as comparedwith the use of horizontally arranged tabs as distinguished from thevertically positioned tabs described. With this feature in mind it willalso be appreciated that by vertically positioning the tabs a block ofspecified dimensions may accommodate a larger number of tabs for Wirelead termination.

Obviously certain modifications and variations of the invention ashereinbet'ore set forth may be made without departing from the spiritand scope thereof, and therefore only such limitations should be imposedas are indicated in the appended claims.

I claim:

1. A terminal connector block comprising a base member formed with alongitudinally extending slot in communication with a plurality ofradially directed electrical service lead receiving recesses extendingto a side margin of said block, a plurality of longitudinally flatconductor tabs formed with endmost lead attachment tongues extending inupright side supported'relation transversely of said slot with saidtongues in said recesses, at least the top side portion of each of saidtabs which is in said slot being formed with amarginal groove, a wiresegment extending along said slot adjacent the top thereofinterconnecting at least some of said tabs with portions thereof snuglyreceived in said grooves, and top cover means attached to said basemember to enclose said tabs and Wire segment therein.-

2. A terminal connector block comprising a base member formed with alongitudinally extending slot in communication with a plurality ofradially directed electrical service lead receiving recesses extendingto aside margin of said block, the base of said slot being formed withan upstanding bead, a plurality of conductor tabs formed with relativelyflat upright mounting portions and endmost lead attachment tonguesextending transversely of said slot with said tongues in said recesses,the mounting portions of said tabs in said slot beingformed withopposite marginal semi-circular grooves, said bead being received in oneof said grooves of each tab to position the same in said block, a wiresegment extending along said slot adjacent the top thereofinterconnecting at least some of said tabs with portions thereof snuglyreceived in the other of said grooves, and top cover means attached tosaid base member to enclose said tabs and wire segment therein.

References Cited in the file of this patent UNITED STATES PATENTS1,934,945 Merlau et al. Nov. 14, 1955 2,747,144 Beers May 22, 19562,820,211 Batcheller Jan. 14, 1958 2,924,808 Hewes et a1. Feb. 9, 1960FOREIGN PATENTS 114,796 Austria Oct. 25, 1929

1. A TERMINAL CONNECTOR BLOCK COMPRISING A BASE MEMBER FORMED WITH A LONGITUDINALLY EXTENDING SLOT IN COMMUNICATION WITH A PLURALITY OF RADIALLY DIRECTED ELECTRICAL SERVICE LEAD RECEIVING RECESSES EXTENDING TO A SIDE MARGIN OF SAID BLOCK, A PLURALITY OF LONGITUDINALLY FLAT CONDUCTOR TABS FORMED WITH ENDMOST LEAD ATTACHMENT TONGUES EXTENDING IN UPRIGHT SIDE SUPPORTED RELATION TRANSVERSELY OF SAID SLOT WITH SAID TONGUES IN SAID RECESSES, AT LEAST THE TOP SIDE PORTION OF EACH OF SAID TABS WHICH IS IN SAID SLOT BEING FORMED WITH A MARGINAL GROOVE, A WIRE SEGMENT EXTENDING ALONG SAID SLOT ADJACENT THE TOP THEREOF INTERCONNECTING AT LEAST SOME OF SAID TABS WITH PORTIONS THEREOF SNUGLY RECEIVED IN SAID GROOVES, AND TOP COVER MEANS ATTACHED TO SAID BASE MEMBER TO ENCLOSE SAID TABS AND WIRE SEGMENT THEREIN. 